Drills, in particular, hammer drills, comprise a main housing in which is mounted a spindle and a motor, which rotatingly drives the spindle via gears and/or a hammering mechanism, also located within the housing. The spindle transfers the rotational movement of the spindle or the impacts of the hammer mechanism to a cutting tool, such as a drill bit, via a chuck or tool holder attached to the end of the spindle, forward of the main housing.
Typically, such drills have two handles: a rear handle attached at the rear of the main housing and a side handle attached towards the front of the main housing, on one side of or below the main housing. Often, the side handle can be attached in a range of angular positions on the main housing.
One type of side handle comprises a hand grip which is attached at one end to a base, which in turn is attached to the side of the main housing of the drill. The hand grip typically extends away from the base and the housing in a direction generally perpendicular to the longitudinal axis of the spindle of the drill.
A problem with power tools, in particular drills, is that they generate a large amount of vibration during their operation. It is desirable to minimize the amount of vibration transferred. One way of achieving this is to provide a vibration dampener between the hand grip and the base to reduce the amount of vibration transferred from the base to the hand grip.
European Patent Document No. EP2082846, as published, describes such a design of side handle for a drill in paragraphs 45 to 52 with reference to FIGS. 7 to 13. The side handle comprises a hand grip 84 (using the same reference numbers as EP2082846) which is attached to a bolt 106 via two vibration dampeners 118, 120. The bolt 106 attaches to a base 80. The dampeners 118, 120 are made from resilient rubber. The structure of the side handle disclosed in EP2082846 is complex and difficult to assemble.
United Kingdom Patent Document No. GB2495758 provides an alternative design of side handle comprising a vibration dampener. However, the design utilizes a complex metal spring comprising a central hexagonal plate with six resiliently deformable integral arms to damp the vibration resulting in a complicated structure which is difficult to assemble.
The present invention seeks to provide a side handle having a more simplified structure than the side handles disclosed in EP2082846 and GB2495758.